Articulating dome gimbal assembly

ABSTRACT

A dome protects an articulating gimbal that orients a line-of-sight of a laser beam. The dome is mounted on a host and encloses the articulating gimbal. The dome has first and second shells. The first shell is rotatable about a first axis relative to the host, and the second shell is disposed on the first shell and is rotatable about a second axis relative to the first shell. A first actuator is coupled to the first shell and is configured to rotate the first shell about the first axis relative to the host. A second actuator is coupled to the second shell and is configured to rotate the second shell about the second axis relative to the first shell. A controller is coupled to the first and second actuators and is configured to match the rotation of the first and second shells to the line-of-sight of the laser beam.

BACKGROUND OF THE DISCLOSURE

A beam director can be used on a vehicle, aircraft, structure, or othercomponent and can direct a laser beam toward a desired target. To allowthe beam director to have a more extensive line-of-sight, the beamdirector is directly mounted on the component and is exposed to theenvironment. For example, FIG. 10 illustrates a common configuration ofa beam director 20 used on a component 10.

The beam director 20 includes a base 22 mounted to the host component10. The beam director 20 shown here has a two-axis gimbal structurehaving a yoke 24 and a payload body 26. The yoke 24 of the gimbalstructure can rotate relative to the base 22 about an azimuthal or panaxis Az. The payload body 26 is supported in the yoke 24 to be rotatedtherewith. For its part, the payload body 26 can rotate relative to theyoke 24 about an elevation or tilt axis Ev.

As will be appreciated, a motor, bearings, seals, and the like (notshown) are used for the rotation between the yoke 24 and the base 22.Likewise, another motor, bearings, seals, and the like (not shown) areused for the rotation between the payload body 26 and the yoke 24. Thepayload body 26 houses all of the optical components of the beamdirector 20 therein and supports a protective window optic 28 from whichthe laser beam can be emitted. All of the internal optical components,motors, bearings, and the like need to be properly housed in protectivehousings to avoid environmental exposure. This increases the weightrequired for the beam director 20, which increases the torque requiredfor rotation and increases the size of the motors.

Additionally, wind forces bear directly on the gimbal structure of thebeam director 20, requiring more robust protective housing. The motorsfor the gimbal structure must therefore be up-sized to addressunbalanced wind forces, leading to increased weight and increased powerconsumption.

Furthermore, the seals incorporated into the gimbal axes must be robustbecause the path of the high-energy laser beam inside the payload body26 must be free of contaminants, including humidity and dust. Theseseals to keep any liquids, moisture, sand, and dust out of the beamdirector 20 can be large sources of friction that oppose the gimbalmotion. This friction is an issue for precise motion control, leading tohigh residual jitter and high following error, both of which reduce theefficiency of the beam director 20.

Finally, the payload body 26 carries the exit window 28 at an extremeposition. This window 28 is the largest, heaviest optic of the opticalsystem and is the furthest optic in the optic train. The cantileveredmass of the exit window 28 causes sag due to the force of gravity. Thiscan lead to optical misalignment, which reduces the exit beam qualityand thus reduces the efficiency of the beam director. Opticalmisalignment can be reduced by increasing the stiffness of the beamexpander structure, but this would lead to an increased weight of thebeam director 20, which also increases motor size.

As will be appreciated, moving and controlling a beam director withprecision can be hindered when increased size, weight, and power arerequired. The subject matter of the present disclosure is directed toovercoming, or at least reducing the effects of, one or more of theproblems set forth above.

SUMMARY OF THE DISCLOSURE

In one embodiment, a structure is disclosed for protecting anarticulating gimbal mounted on a host. The articulating gimbal isconfigured to orient a first line-of-sight of a laser beam. Thestructure comprises a dome, a first actuator, a second actuator, and acontroller. The dome is mounted on the host and encloses thearticulating gimbal. The dome has first and second shells. The firstshell is rotatable about a first axis relative to the host. The secondshell is disposed on the first shell and is rotatable about a secondaxis relative to the first shell, the second shell having a firstwindow. The first actuator is coupled to the first shell and isconfigured to rotate the first shell about the first axis relative tothe host. The second actuator is coupled to the second shell and isconfigured to rotate the second shell about the second axis relative tothe first shell. The controller is coupled to the first and secondactuators and is configured to actuate the first and second actuators toposition the first window in the first line-of-sight of the laser beam.

In another embodiment, a structure is disclosed herein for protecting anarticulating gimbal mounted on a host. Again, the articulating gimbal isconfigured to orient a first line-of-sight of a laser beam. Thestructure comprises a first dome shell, a first seal, a first actuator,a second dome shell, a second seal, a second actuator, and a controller.The first dome shell is mounted on the host and encloses a first portionof the articulating gimbal. The first shell has a first edge disposedthereabout and defines a first opening therein. The first seal isdisposed between the first edge of the first shell and the host. Thefirst actuator is coupled to the first dome shell and is configured torotate the first shell on the first edge about a first axis relative tothe host.

The second dome shell is mounted in the first opening of the first domeshell and encloses a remaining portion of the articulating gimbal. Thesecond dome shell has a second edge disposed thereabout and has a firstwindow therein. The second seal is disposed between the second edge ofthe second dome shell and the first opening of the first dome shell. Thesecond actuator is coupled to the second dome shell and is configured torotate the second dome shell on the second edge about a second axisrelative to the first dome shell. The controller is coupled to the firstand second actuators and is configured to actuate the first and secondactuators to position the first window in the first line-of-sight of thelaser beam.

In another embodiment, a structure is disclosed herein for protecting anarticulating gimbal mounted on a base. The articulating gimbal isconfigured to position a beam director optical element. The structurecomprises a dome shell, a first seal, a first actuator, a sphericalsegment shell, a second seal, a second actuator, and a controller. Thedome shell is mounted on the base and encloses the articulating gimbal.The dome shell defines a spherical segment opening and has a first edge.The first seal is disposed between the first edge of the dome shell andthe base. The first actuator is coupled to the dome shell and isconfigured to articulate the dome shell about a first axis relative tothe base.

The spherical segment shell is mounted in the spherical segment openingof the dome shell and encloses the articulating gimbal. The sphericalsegment shell has a window and having a second edge. The second seal isdisposed between the second edge of the spherical segment shell and thespherical segment opening of the dome shell. The second actuator iscoupled to the spherical segment shell and is configured to articulatethe spherical segment shell about a second axis relative to the domeshell. The controller is coupled to the first and second actuators andis configured to actuate the first and second actuators to position thefirst window in the first line-of-sight of the laser beam.

An apparatus disclosed herein can be used on a host. The apparatuscomprises an articulating gimbal and comprises a structure according tothe embodiment disclosed above for protecting the articulating gimbal.

The foregoing summary is not intended to summarize each potentialembodiment or every aspect of the present disclosure.

BRIEF DESCRIPTION OF THE DRAWINGS

FIGS. 1A-1B illustrate an articulating dome shell according to thepresent disclosure for a beam director in two orientations.

FIGS. 2A-2B illustrate one embodiment of an articulating dome shellaccording to the present disclosure in two orientations.

FIGS. 3A-3B illustrate another embodiment of an articulating dome shellaccording to the present disclosure in two orientations.

FIGS. 4A-4B illustrate yet another embodiment of an articulating domeshell according to the present disclosure in two orientations.

FIGS. 5A-5B illustrate an additional embodiment of an articulating domeshell according to the present disclosure in two orientations.

FIG. 6A illustrates a schematic of actuators for the articulating domeshell according to FIGS. 2A-2B.

FIG. 6B illustrates a schematic of actuators for the articulating domeshell according to FIGS. 3A-3B.

FIG. 6C illustrates a schematic of actuators for the articulating domeshell according to FIGS. 4A-4B.

FIGS. 7A-7C illustrate examples of an articulating gimbal and beamexpander of a laser source for use with the disclosed articulating domeshell.

FIG. 8A illustrates a control system for the articulating dome shellaccording to FIGS. 2A-2B and 4A-4B.

FIG. 8B illustrates a control system for the articulating dome shellaccording to FIGS. 3A-3B.

FIG. 8C illustrates a control system for the articulating dome shellaccording to FIGS. 5A-5B having a beam director according to FIG. 7C.

FIGS. 9A-9B illustrate a range of possible articulating dome envelopeshapes.

FIG. 10 illustrates a common configuration of a beam director.

DETAILED DESCRIPTION OF THE DISCLOSURE

FIGS. 1A-1B illustrate a beam director assembly 30 of the presentdisclosure having an articulating dome shell 50 enclosing anarticulating gimbal 40. The assembly 30 is shown in two orientations.(The articulating gimbal 40 is only shown schematically). The dome shell50 mounts to a host component 10, which can be a vehicle, an aircraft, astationary structure, or the like, and the dome shell 50 encloses thearticulating gimbal 40 mounted inside the dome shell 50. The dome shell50 includes a primary dome 52, a secondary dome 54, and a protectiveoptic 56. The radius of the shell 50 may only need to be slightly largerthan the swept radius for the articulating gimbal 40 housed inside.

Briefly, the dome shell 50 acts as a structure for protectingarticulating gimbal 40 mounted on the host component 10. Thearticulating gimbal 40 is configured to orient a line-of-sight (LOS) ofa laser beam. The primary dome 52 is rotatable about a first axisrelative to the host component 10. The secondary dome 54 is disposed onthe primary dome 52 and is rotatable about a second, carried axisrelative to the primary dome 52. The secondary dome 54 has a window withthe protective optics 56. A first actuator (not shown) coupled to theprimary dome 52 is configured to rotate the primary dome 52 about thefirst axis relative to the host component 10. Meanwhile, a secondactuator (not shown) coupled to the secondary dome 54 is configured torotate the secondary dome 54 about the second axis relative to theprimary dome 52. A controller or control system 70 coupled to the firstand second actuators is configured to actuate the first and secondactuators to position the protective optic 56 in the line-of-sight ofthe laser beam.

More particularly, the primary dome 52 has an environmental seal 53along its edge with the host component 10. The secondary dome 54 of thedome shell 50 is carried by the primary dome 52 and has an environmentalseal 55 along its edge with the primary dome 52. The protective optic orwindow 56 is disposed on the secondary dome 54.

During operation, the primary dome 52 can be articulated about anazimuthal or pan axis Az to match the rotation of the articulatinggimbal 40 about the azimuth Az. This movement moves the secondary dome54 and the protective optic 56. During operation, the secondary dome 54can be separately or concurrently articulated about an elevation or tiltaxis Ev to match the rotation of the articulating gimbal 40 about theelevation Ev. This movement also moves the protective optic 56. Becausethe rotation of the secondary dome 54 on the primary dome 52 alsoproduces changes in the azimuthal axis, coordination between therotation about the two axes Az and Ev may be necessary as noted below.

The shell 50 (and its associated motion system) encounters friction fromthe environment seals 53, 55, but the articulating gimbal 40 housedinside does not need to move against that friction. Additionally, theshell 50 (and its associated motion system) carries the protective optic56, which is typically the largest, heaviest optic of the opticalsystem. However, the articulating gimbal 40 housed inside the shell 50does not need to carry and move the optic 56 so movement and control ofthe articulating gimbal 40 are greatly simplified.

Preferably, the dome shell 50 is moved independently of the articulatinggimbal 40 enclosed in the shell 50. In this way, the two components 40and 50 of the assembly 30 can be moved independently from one anotherwithout a physical connection between them. Thus, actuators (not shown)to move the articulating gimbal 40 do not need to be sized and poweredto also move the dome shell 50 and visa-versa. Instead, coordinatedmovement is achieved through simultaneous control of separate actuators(not shown). The coordinated control can be continuous, meaning that theprotective optic 56 is moved in unison with the direction of thearticulating gimbal 40 so that the line-of-sight of the articulatinggimbal 40 is maintained aligned with the optic axis of the protectiveoptic 56. In this way, the motion of the domes 52, 54 are synchronizedwith the gimbal motion of the articulating gimbal 40 to keep theprotective optic 56 aligned with the line-of-sight of the articulatinggimbal 40.

Other forms of operation are possible. For example, instead ofcontinuous alignment, the two components 40 and 50 can be moved throughseparate paths to aligned endpoints where the protective optic 56 andthe articulating gimbal 40 are aligned. Here, the optic 56 andarticulating gimbal 40 may not be aligned during movement between theendpoints.

The articulating dome shell 50 is preferably composed of a lightweight,protective material. For example, the primary dome 52 and the secondarydome 54 can be composed of a lightweight metal, plastic, or compositematerial that provides environmental protection to the articulatinggimbal (40) enclosed in the shell 50.

As can be seen, the motion of the shell's domes 52, 54 encountersfriction from the environmental seals 53, 55. This simplifies thestructural requirements, motion, and control for the articulating gimbal40. In this way, residual jitter and following error of the articulatinggimbal's line-of-sight can be reduced. By off-loading the sealingfunction to the environmental seals 53, 55, the friction on the gimbalof the articulating gimbal 40 is greatly reduced, allowing significantimprovement (decrease) in line-of-sight residual jitter and followingerror. The reduction in line-of-sight residual jitter and followingerror also enables more precise maintenance of high-energy laser poweron a target, improving the efficiency of the beam director assembly 30.

Overall weight of the beam director assembly 30 is reduced. Thearticulating dome shell 50 is lightweight with no structural functionother than acting as a protective enclosure. By shielding thearticulating gimbal 40 and its gimbal from the environment using thearticulating dome 50, the articulating gimbal 40 and its gimbal can takean open, skeletal form. The weight reduction also reduces the massmoment of inertia, reducing weight for actuators on the articulatinggimbal 40. The weight reduction makes the assembly 40 more transportableand adaptable to a greater variety of platforms.

Moreover, any gravity sag that would be caused by carrying theprotective optic 56 on the articulating gimbal 40 is eliminated. Bysupporting the weight of the optic 56 on the articulating dome 50,optical misalignment due to sag of the articulating gimbal 40 is greatlyreduced, improving beam quality and therefore system efficiency.

Just as important, wind loading on the gimbal structure of thearticulating gimbal 40 is eliminated. Eliminating wind loading as atorque disturbance leads to reduced residual jitter and following error(thus improving efficiency) and also leads to reduced weight becausegimbal actuators do not need to be sized to overcome unbalanced windforces.

Eye safety can also be improved while thermal deformation is decreased.High-energy laser systems emit stray light as a necessary consequence oftheir optical systems. The stray light poses an eye-safety hazard. Theinterior surface 51 of the dome 50 can have a high-reflectivity coating,such as gold coating, to manage stray light.

The high-reflectivity coating on the interior surface 51 of thearticulating dome 50 can cause any stray light to execute multipleinternal reflections inside the dome 50 before escaping via theprotective optic 56. The internal reflections of the stray light createan integrating sphere effect that leads to an extremely wide divergenceof exiting stray light, greatly reducing the nominal ocular hazarddistance. The even stray light distribution creates no hot spots on thearticulating gimbal 40 and articulating gimbal structure, preservingoptical alignment.

FIGS. 2A-2B illustrate one embodiment of an articulating dome shell 50Aaccording to the present disclosure in two orientations. This dome shell50A is similar to that discussed above with respect to FIGS. 1A-1B. Asbefore, the dome shell 50A includes a primary dome 52, a secondary dome54, and a protective optic 56. Although not shown here, an articulatinggimbal (40) with its gimbal structure and beam expander is housed insidethe dome shell 50A.

Axes are shown in FIGS. 2A-2B to show the movement of the domes 52, 54of the shell 50A. The primary dome 52 can be rotated about an azimuthalor pan axis Az. When the primary dome 52 is rotated, the secondary dome54 having the protective optic 56 is also rotated about the azimuthalAz. The line-of-sight for the beam from the optic 56 can thereby haveits direction changed along the azimuth.

The secondary dome 54 can be rotated about a carried axis Az+Ev. Whenthe secondary dome 54 is rotated, the azimuthal Az and elevation Ev ofthe protective optic 56 change together. Therefore, to have theelevation of the line-of-sight for the beam from the optic 56 change,corrective adjustments to the azimuth of the primary dome 52 will benecessary. These motions can be coordinated through straightforwardgeometric equations.

FIGS. 3A-3B illustrate another embodiment of an articulating dome shell50B according to the present disclosure in two orientations. This domeshell 50B is similar to that discussed above with respect to FIGS. 2A-2Bin that the shell 50B includes a primary dome 52, a secondary dome 54,and a protective optic 56. Here, an additional element of the dome shell50B includes a window bezel 58 that encloses the protective optic 56.This bezel 58 includes an environmental seal along its edge 59 with thesecondary dome 54. Secondary optics 57 are disposed in the bezel 58 withrespect to the centrally located protective optic 56 inside the bezel58. This bezel 58 can be rotated relative to the secondary dome 54 abouta roll axis R so that the orientation of the optics 56, 57 can also bechanged.

For example, high-energy laser systems may require the use of auxiliarysensors co-aligned with the main high-energy laser beam. The auxiliarysensors are typically carried in a piggyback fashion on the structure ofthe articulating gimbal (40). The additional optics 57 adjacent the mainoptic 56 shown here provide windows for these types of auxiliarysensors. Although such sensors could use the same optic 56 as for thelaser beam, the sensors in many instances require different filtering orprotection than the beam for the main optic 56. Therefore, separateoptics 57 of different materials, filtering, and other qualities aretypically needed. The rotating bezel 58 is mechanized by a thirdactuator (not shown) so alignment can be adequately controlled tocompensate for the rotation introduced by the dome's movements.

FIGS. 4A-4B illustrate yet another embodiment of an articulating domeshell 50C according to the present disclosure in two orientations. Thedome shell 50C includes a primary dome 52′ that has a wide dome slit orspherical segment opening. This wide dome slit is covered by a sphericalsegment shell, a bellows, or an overlapping leaf set 54′, which ismounted in the wide dome slit. The leaf set 54′ seals with the primarydome 52′ and carries a protective optic 56.

During operation, the primary dome 52′ can be articulated about anazimuthal axis Az to match the rotation of the articulating gimbal (40)enclosed therein about the azimuth Az. This movement moves the leaf set54′ and the protective optic 56. During operation, the leaf set 54′ canbe articulated about an elevation or altitude axis Ev to match therotation of the articulating gimbal (40) about the elevation Ev. Thismovement moves the protective optic 56. Here, rotation of the leaf set54′ in the dome's slit on the primary dome 52′ does not produce changesin the azimuthal axis because the dome's slit having the leaf set 54′lies preferably on a central division of the primary dome 52′.

As shown, the leaf set 54′ can include a plurality of interleaved slats54 a-b on both sides of the protective optic 56. These interleaved slats54 a-b expand and contract with the movement of the leaf set 54′ as theelevation of the protective optic 56 is changed. In this sense, theinterleaved slats 54 a-b act as an accordion or bellows structureenclosing the interior of the shell 50C while the protective optic 56 ismoved consistent with an elevation-over-azimuth articulating gimbal (40)inside the dome shell 50C.

FIGS. 5A-5B illustrate yet another embodiment of an articulating domeshell 50D according to the present disclosure in two orientations. Thisdome shell 50D is similar to that shown in FIGS. 3A-3B in that itincludes a primary dome 52, a secondary dome 54, and a protective optic56. Here, instead of including a window bezel (i.e., 58 of FIGS. 3A-3B)that encloses the protective optic 56 and has secondary optics 57, thesecond dome 54 includes the secondary optics 57 in a fixed positionadjacent the protective optic 56. Therefore, the orientation of thesecondary optics 57 relative to the protective optic 56 is not changed.Instead, the gimbal structure of the internal articulating gimbal (40)can include a roll axis that would allow any ancillary sensors on thearticulating gimbal (40) to be aligned with these secondary optics 57during movement.

The dome shells 50 of FIGS. 1A through 5B have been generally depictedas being hemispheres. Accordingly, the line-of-sight can be as much as360-degrees along the azimuth Az and 180-degrees along the elevation Ev.The dome shells 50 can be less than a hemisphere if less elevation isneeded, such as shown in FIG. 9A. Likewise, if line-of-sight needs topoint below the horizon at greater elevation angles, then the dome shell50 can extend to a fuller portion of a sphere greater than a hemisphere,such as shown in FIG. 9B. Additionally, other shapes can be used, suchas a dome shell having a cylindrical base portion as shown in FIG. 9C.

FIG. 6A illustrates a schematic of actuators for the articulating domeshell 50A according to FIGS. 2A-2B. A main actuator 62 engages an edgeor rim 53′ for the primary dome (52) so that actuation of the mainactuator 62 rotates the primary dome (52) along the azimuth axis Az,which changes the azimuth of the protective optic 56. A secondaryactuator 64 carried by the primary dome (52) engages an edge or rim 55′for the secondary dome (54) so that the actuation of the secondaryactuator 64 rotates the secondary dome (54) along a carried axis, whichchanges the elevation Ev and azimuth Az of the protective optic 56.

Various types of actuators 62, 64 and mechanical arrangements of gears,bearings, belts, and the like can be used. For example, a first electricmotor 62 can rotate a pinion gear engaged with a rack gear about the rim53′ of the primary dome 52, and a second electric motor 64 carried bythe primary dome 52 can rotate a pinion gear engaged with a rack gearabout the rim 55′ of the secondary dome 52. Because power for the secondelectric motor 64 must be carried through the main rim 53′, slip ringsalong the rim 53′ can provide power across the articulating elements ofthe domes 52, 54. The motors for the actuators 62, 64 may need to behigh-torque, but the precision does not need to be as high as requiredfor the articulating gimbal 40.

FIG. 6B illustrates a schematic of actuators for the articulating domeshell 50B according to FIGS. 3A-3B. A main actuator 62 engages an edgeor rim 53′ for the primary dome (52) so that actuation of the mainactuator 62 rotates the primary dome (52) along the azimuth axis Az,which changes the azimuth of the protective optic 56. A secondaryactuator 64 carried by the primary dome (52) engages an edge or rim 55′for the secondary dome (54) so that the actuation of the secondaryactuator 64 rotates the secondary dome (54) along a carried axis, whichchanges the elevation Ev and azimuth Az of the protective optic 56.Finally, a third actuator 68 carried by the secondary dome (54) engagesan edge or rim 59 for the bezel 58 so that actuation of the thirdactuator 68 rotates the bezel 58 along a roll axis R, which changes theorientation of the protective optics 56 and 57.

FIG. 6C illustrates a schematic of actuators for the articulating domeshell 50C according to FIGS. 4A-4B. A main actuator 62 engages an edgeor rim 53′ for the primary dome (52) so that actuation of the mainactuator 62 rotates the primary dome (52) along the azimuth axis Az,which changes the azimuth of the protective optic 56. A secondaryactuator 64 carried by the primary dome (52) engages an edge or rim 55′for the wide dome slit having the leaf set (54′) so that actuation ofthe secondary actuator 64 extends or retracts covering across the widedome slit by the leaf set (54′) about an elevation axis Ev, whichchanges the elevation of the protective optic 56.

Various structures can be used for the articulating gimbal and beamexpander for the internal components of the beam director assembly ofthe present disclosure. For example, FIG. 7A illustrates one type ofarticulating gimbal 40A for use with the disclosed articulating domeshell (50). This articulating gimbal 40A uses an elevation-over-azimuth(Alt-Az) type of gimbal structure. A base actuator 33′ rotates amounting bracket swivel 32 about an azimuthal or pan axis Az. Forkedarms 34 on the mounting bracket swivel 32 support a payload body 36.Using a carried actuator 35′ on the swivel 32, the payload body 36 canbe rotated about an orthogonal axis 35 to change the elevation or tiltaxis Ev of the payload body 36. Because the articulating gimbal 40A isenclosed and protected in a dome shell (50) according to the presentdisclosure, the articulating gimbal 40A does not require extensivehousing protections, seals, and other structures. Instead, thearticulating gimbal 40A and the optical train for the beam can beconfigured with a frame and can have an open skeletal structure, whichreduces weight and inertia. As a consequence, the articulating gimbal40A can be moved more accurately and efficiently with such a structure.

As schematically shown, the optical train on the articulating gimbal 40Acan include a laser source 42 on the payload body 36 and can includeoptics 44, such as curved mirrors, lenses, and the like, supported on abeam expander structure 46 constructed as a frame adjacent the lasersource 42. These and other forms of structures can be used for theoptical train and the articulating gimbal 40A. Notably, a heavyprotective optic (not shown) does not need to be cantilevered at thedistal end of the beam expander structure 46 because such a protectiveoptic is supported on the enclosing dome shell, as discussed previously.If the laser source 42 is not on the payload body 36, the laser source42 may be off-gimbal below the base actuator 33′, and its beam may beconventionally transported via coudé optics enclosed within the forkedarms 34.

FIG. 7B illustrates another type of articulating gimbal 40B for use withthe disclosed articulating dome shell (50). This articulating gimbal 40Buses an equatorial type of gimbal structure. Many of the componentsshown here are similar to those discussed above. Here, the mountingbracket swivel 32 is rotatable about a polar axis Pol, and the payloadbody 36 is rotated about a declination axis 35 (Dec).

FIG. 7C illustrates yet another articulating gimbal 40C for use with thedisclosed articulating dome shell (50). This articulating gimbal 40Cuses a gimbal structure similar to an elevation-over-azimuth (Alt-Az)type of structure, but includes an additional roll axis R. A baseactuator 33′ rotates a base 32 about an azimuthal axis Az. A mountingswivel 34′ on the base 32 supports a payload body 36, which can berotated about an orthogonal axis 35 by a carried actuator 35′ to changethe elevation Ev of the payload body 36. Meanwhile, the payload body 36and the orthogonal axis 35 are rotatable by another carried actuator 37′and a gear 37 about a roll axis R.

As shown, the beam expander structure 46 can include a secondary opticalcomponent 47, such as a sensor noted previously. Rotation of the payloadbody 36 on the gear 37 about the roll axis R can rotate the orientationof the secondary optical component 47. This configuration can be usefulfor the dome structure 50D of FIG. 5A-5B so the orientation of thesecondary optical component 47 can be aligned and matched to thesecondary optics (57) of the secondary dome (54).

FIG. 8A illustrates a control system 70A for the articulating dome shell50A according to FIGS. 2A-2B. A control unit 72 connects to theactuators for the gimbal 40, including an azimuth actuator 33′ and anelevation actuator 35′. The control unit 72 also connects to theactuators for the articulating dome shell 50A, including an azimuthactuator 62 and an elevation actuator 64. During operation, the controlunit 72 receives inputs of the gimbal's movement to be matched oraligned by the dome shell 50A. If the dome shell 50A is to match themovement of the gimbal 40 along a prescribed trajectory, the controlunit 72 can receive commands specifying the gimbal's path and can thenitself command the matching movements for the dome shell 50Aaccordingly. If only the starting and ending positions of the gimbal 40are specified, then the control unit 72 can control the dome shell 50Aso its ending position matches the gimbal's end position. Either way,the control unit 72 calculates movements of the articulating dome shell50A and implements the movement by controlling the actuators 62, 64. Ifthe control unit 72 is integrated with the gimbal 40, then the controlunit 72 calculates the movements of the gimbal 40 and implements themovement by controlling the actuators 33′, 35′. As noted, adjustments tothe secondary dome (54) on the primary dome (52) produce changes in bothelevation and azimuth of the protective optic (56). The control unit 72can make necessary adjustments to the movement of the dome shell 50Aabout the azimuth and elevation so the protective optic (56) can matchthe orientation of the articulating gimbal 40. These additionaladjustments would not be necessary when this control system 70A is usedwith the dome shell 50C of FIGS. 4A-4B.

FIG. 8B illustrates a control system 70B for the articulating dome shell50B according to FIGS. 3A-3B. As before, a control unit 72 connects tothe actuators for the articulating gimbal 40, including an azimuthactuator 33′ and an elevation actuator 35′. The control unit 72 alsoconnects to the actuators for the articulating dome 50B, including anazimuth actuator 62, an elevation actuator 64, and a window actuator 68.During operation, the control unit 72 receives inputs of the gimbal'smovement to be matched or aligned by the dome shell 50B. If the domeshell 50B is to match the movement of the gimbal 40 along a prescribedtrajectory, then the control unit 72 can receive commands specifying thegimbal's path and can then itself command the matching movements of thedome shell 50B accordingly. If only the starting and ending positions ofthe gimbal 40 are specified, then the control unit 72 can control thedome shell 50B so its ending position matches the gimbal's end position.Either way, the control unit 72 calculates movements of the articulatingdome shell 50B and implements the movement by controlling the actuators62, 64, 68. If the control unit 72 is integrated with the gimbal 40,then the control unit 72 calculates the movements of the gimbal 40 andimplements the movement by controlling the actuators 33′, 35′.

As noted, adjustments to the secondary dome (54) on the primary dome(52) produce changes in both elevation and azimuth of the protectiveoptic (56). The control unit 72 can make necessary adjustments to themovement of the dome shell 50B about the azimuth and elevation so theprotective optic (56) can match the orientation of the articulatinggimbal 40. As also noted, secondary optics 57 on the bezel (58) of thedome shell 50B need to be aligned with the secondary optical elements(47) on the beam expander on the gimbal 40. The control unit 72 canrotate the bezel (58) so that the optics (57) can match and remainaligned with the optical elements (47) on the gimbal 40.

FIG. 8C illustrates a control system 70C for the articulating dome shell50D according to FIGS. 5A-5B having a beam director according to FIG.7C. As before, a control unit 72 connects to the actuators for thegimbal 40, which here include an azimuth actuator 33′, an elevationactuator 35′, and a rotational actuator 37′. The control unit 72 alsoconnects to the actuators for the articulating dome shell 50D, includingan azimuth actuator 62 and an elevation actuator 64. During operation,the control unit 72 receives inputs of the gimbal's movement to bematched or aligned by the dome shell 50D. If the dome shell 50D is tomatch the movement of the gimbal 40 along a prescribed trajectory, thenthe control unit 72 can receive the gimbal's path and then itselfcommand the dome shell 50D matching movements accordingly. If the domeshell 50D is intended to align with the articulating gimbal 40 atendpoint positions, then the control unit 72 can control the dome shell50D so its ending position matches the gimbal's end position. Eitherway, the control unit 72 calculates movements of the articulating domeshell 50D and implements the movement by controlling the actuators 62,64. If the control unit 72 is integrated with the gimbal 40, then thecontrol unit 72 calculates the movements of the gimbal 40 and implementsthe movement by controlling the actuators 33′, 35′, 37′.

As noted, adjustments to the secondary dome (54) on the primary dome(52) may produce changes in both elevation and azimuth of the protectiveoptic (56). The control unit 72 can make necessary adjustments to themovement of the dome shell 50D about the azimuth and elevation so theprotective optic (56) can match the orientation of the articulatinggimbal 40. As also noted, secondary optics 57 on the dome shell 50D needto be aligned with the secondary optical elements (47) on the beamexpander structure (46) of the gimbal 40. Here, the dome shell 50D maylack the rotatable bezel (58) having the optics 56, 57. Instead, thecontrol unit 72 can rotate the beam expander structure (46) about theroll axis R so the optical elements (47) can match and remain alignedwith the secondary optics (57).

The foregoing description of preferred and other embodiments is notintended to limit or restrict the scope or applicability of theinventive concepts conceived of by the Applicants. It will beappreciated with the benefit of the present disclosure that featuresdescribed above in accordance with any embodiment or aspect of thedisclosed subject matter can be utilized, either alone or incombination, with any other described feature, in any other embodimentor aspect of the disclosed subject matter.

1. A structure for protecting an articulating gimbal mounted on a host,the articulating gimbal being configured to orient a first line-of-sightof a laser beam, the structure comprising: a dome mounted on the hostand enclosing the articulating gimbal, the dome having first and secondshells, the first shell being rotatable about a first axis relative tothe host, the second shell disposed on the first shell and beingrotatable about a second axis relative to the first shell, the secondshell having a first window; a first actuator coupled to the first shelland being configured to rotate the first shell about the first axisrelative to the host; a second actuator coupled to the second shell andbeing configured to rotate the second shell about the second axisrelative to the first shell; and a controller coupled to the first andsecond actuators and being configured to actuate the first and secondactuators to position the first window in the first line-of-sight of thelaser beam.
 2. The structure of claim 1, wherein the second shelldefines an opening therein; and wherein the window comprises aprotective optic mounted in the opening.
 3. The structure of claim 1,the articulating gimbal having an ancillary optical element having asecond line-of-sight adjacent the laser beam, wherein the second shelldefines an opening therein; wherein the first window comprises: a bezelmounted in the opening and having an outer edge and an inner edge, thebezel having an ancillary window; a protective optic mounted in theinner edge of the bezel; and a third actuator coupled to the bezel andbeing configured to articulate the bezel about a third axis relative tothe second shell; and wherein the controller is further coupled to thethird actuator and is configured to actuate the third actuator toposition the second window in the second line-of-sight of the ancillaryoptical element.
 4. The structure of claim 1, wherein the controller iscoupled to third actuators of the articulating gimbal and is configuredto receive feedback of articulation of the articulating gimbal from thethird actuators, the controller being configured to coordinate theactuation of the first and second actuators to the feedback of thearticulation of the articulating gimbal.
 5. The structure of claim 1,wherein the controller is coupled to third actuators of the articulatinggimbal and is configured to control articulation of the articulatinggimbal by the third actuators.
 6. An apparatus for use on a host, theapparatus comprising: an articulating gimbal configured to mount on thehost, the articulating gimbal having at least two gimbal actuators andbeing configured to orient a line-of-sight of a laser beam; and astructure according to claim 1 for protecting the articulating gimbal.7. A structure for protecting an articulating gimbal mounted on a host,the articulating gimbal being configured to orient a first line-of-sightof a laser beam, the structure comprising: a first dome shell mounted onthe host and enclosing a first portion of the articulating gimbal, thefirst shell having a first edge disposed thereabout and defining a firstopening therein; a first seal disposed between the first edge of thefirst shell and the host; a first actuator coupled to the first domeshell and being configured to rotate the first shell on the first edgeabout a first axis relative to the host; a second dome shell mounted inthe first opening of the first dome shell and enclosing a remainingportion of the articulating gimbal, the second dome shell having asecond edge disposed thereabout and having a first window therein; asecond seal disposed between the second edge of the second dome shelland the first opening of the first dome shell; a second actuator coupledto the second dome shell and being configured to rotate the second domeshell on the second edge about a second axis relative to the first domeshell; and a controller coupled to the first and second actuators andbeing configured to actuate the first and second actuators to positionthe first window in the first line-of-sight of the laser beam.
 8. Thestructure of claim 7, wherein the first and second dome shells are eachcomposed of a material selected from the group consisting of a metalmaterial, a plastic material, and a composite material.
 9. The structureof claim 7, wherein the second dome shell defines a second openingtherein; and wherein the first window comprises a protective opticmounted in the second opening.
 10. The structure of claim 7, thearticulating gimbal having an ancillary optical element having a secondline-of-sight adjacent the laser beam, wherein the second dome shelldefines a second opening therein; wherein the first window comprises: abezel mounted in the second opening and having an outer edge and aninner edge, the bezel having an ancillary window; a protective opticmounted in the inner edge of the bezel; a third seal disposed betweenthe outer edge of the bezel and the second opening of the second domeshell; and a third actuator coupled to the bezel and being configured toarticulate the bezel on the outer edge about a third axis relative tothe second dome shell; and wherein the controller is further coupled tothe third actuator and is configured to actuate the third actuator toposition the second window in the second line-of-sight of the ancillaryoptical element.
 11. The structure of claim 7, wherein the controller iscoupled to third actuators of the articulating gimbal and is configuredto receive feedback of articulation of the articulating gimbal from thethird actuators, the controller being configured to coordinate theactuation of the first and second actuators to the feedback of thearticulation of the articulating gimbal.
 12. The structure of claim 7,wherein the controller is coupled to third actuators of the articulatinggimbal and is configured to control articulation of the articulatinggimbal by the third actuators.
 13. The structure of claim 7, wherein thefirst edge circumscribes the first axis about which the first dome shellis rotatable, wherein the first opening is circular, wherein the secondedge circumscribes the second axis about which the second dome shell isrotatable.
 14. The structure of claim 7, wherein the first opening isoffset from the first axis about which the first dome shell isrotatable; and wherein the first window of the second dome shell isoffset from the second axis about which the second dome shell isrotatable.
 15. An apparatus for use on a host, the apparatus comprising:an articulating gimbal configured to mount on the host, the articulatinggimbal having at least two gimbal actuators and being configured toorient a line-of-sight of a laser beam; and a structure according toclaim 7 for protecting the articulating gimbal.
 16. The apparatus ofclaim 15, wherein the articulating gimbal comprises anazimuth-over-elevation gimbal or an equatorial gimbal.
 17. The apparatusof claim 15, wherein the articulating gimbal comprises an ancillaryoptical element having a second line-of-sight adjacent the laser beam;wherein the second dome shell defines a second opening; wherein thefirst window comprises: a bezel mounted in the second opening and havingan outer edge and an inner edge, the bezel having an ancillary window; aprotective optic mounted in the inner edge of the bezel; a third sealdisposed between the outer edge of the bezel and the second opening ofthe second dome shell; and a third actuator coupled to the bezel andbeing configured to rotate the bezel about a third axis relative to thesecond dome shell; and wherein the controller is further coupled to thethird actuator and is configured to actuate the third actuator toposition the second window in the second line-of-sight of the ancillaryoptical element.
 18. The apparatus of claim 15, wherein the articulatinggimbal is configured to orient a second line-of-sight of an ancillaryoptical element about a roll axis relative to the laser beam; whereinthe first window comprises a protective optic for the laser beam; andwherein the second dome shell defines an ancillary window having anotherprotective optic mounted therein for the ancillary optical element. 19.A structure for protecting an articulating gimbal mounted on a base, thearticulating gimbal being configured to position a beam director opticalelement, the structure comprising: a dome shell mounted on the base andenclosing the articulating gimbal, the dome shell defining a sphericalsegment opening and having a first edge; a first seal disposed betweenthe first edge of the dome shell and the base; a first actuator coupledto the dome shell and being configured to articulate the dome shellabout a first axis relative to the base; a spherical segment shellmounted in the spherical segment opening of the dome shell and enclosingthe articulating gimbal, the spherical segment shell having a window andhaving a second edge; a second seal disposed between the second edge ofthe spherical segment shell and the spherical segment opening of thedome shell; a second actuator coupled to the spherical segment shell andbeing configured to articulate the spherical segment shell about asecond axis relative to the dome shell; and a controller coupled to thefirst and second actuators and being configured to actuate the first andsecond actuators to position the first window in the first line-of-sightof the laser beam.
 20. The structure of claim 19, wherein the sphericalsegment shell comprises a plurality of overlapping slats movable betweena stacked condition and an expanded condition.
 21. An apparatus for useon a base, the apparatus comprising: an articulating gimbal configuredto mount on the base, the articulating gimbal being configured toposition a beam director optical element; a structure according to claim19 for protecting the articulating gimbal.